Is the gt37 turbine interchangeable with the gt40? Does the center section differ between both or is it just a larger housing and wheel? Could one swap say the center section and compressor side of a gt37 stock lly onto the turbine side of a gt40? Just curious
Garrett vgt
- Thread starter valleyduramax
- Start date
Center section is the same. You wanna run the 4094 turbine wheel with the 37 compressor wheel and housing?
Thought about it. Not sure how far i want to go with my truck. Gonna fab a set of headers and uppipes and also a new set of intake shells over the winter. Want to make exhaust side as free flowing as possible as i dont count my time as cost. Low drive pressure ratio is basically free power in a sense. And like going outside the box lol
With the large turbine wheel and small inducer wheel you have to worry about overspeeding the shaft and drying out the oil film on the bearings. If that happens the shaft gets too hot and fails. Ask me how I know
Dont plan on pushing it real hard. Just makin it efficient as possible. Yes i realize it might not be the best route but want to keep it simple rather that having to vuy a bunch of stuff i techically cant afford lol. House is more important
I have ran a gt40 rear half and a 64x88mm lly stock front or 11 blade billet.
I have been doing this for over 3 years and multiple turbo's.
They whistle out the turbine like a 6.0. You need to tune it like a 4094 vane map.
The 11 blade wheel does better with an overspeed condition.
Spoolup is very close to stock with good tuning and larger injectors.
egt's and drive pressure ratio is great.
The manifolds/headers and uppipes you want to build will compliment this as well.
It is an expensive combination, but well worth the money in my opinion.
Last year garrett came out with a gtx4088. That is basically a dimension ally identical setup to this turbo with the exception of the variable geometry.
This is a very good choice and I think you will be very happy.
I have been doing this for over 3 years and multiple turbo's.
They whistle out the turbine like a 6.0. You need to tune it like a 4094 vane map.
The 11 blade wheel does better with an overspeed condition.
Spoolup is very close to stock with good tuning and larger injectors.
egt's and drive pressure ratio is great.
The manifolds/headers and uppipes you want to build will compliment this as well.
It is an expensive combination, but well worth the money in my opinion.
Last year garrett came out with a gtx4088. That is basically a dimension ally identical setup to this turbo with the exception of the variable geometry.
This is a very good choice and I think you will be very happy.
Where can i buy the gt40 turbine housing and wheel? That is my next step lol i have a batmowheel and my stock housing is ported and runs good just need something to mod and id like to try this
You can buy the turbine wheel from Danville. You can get your lly housing and center section machined to except the 4094 turbine wheel.
I need the whole turbine housing correct? I thought the vane pivot locations for the gt40 was on a large diameter compared to the gt37
Ok it is expensive becuase you can't just buy the turbine and wheel. lol
You need a core lly turbo. You use the lly center and front, buy an 11 blade or batmo lly wheel, balance it to a gt40 turbine in the lly center housing. Then use the new gt40 turbine housing and vanes.
You will see the difference in the vane design and why the tuning is so drastically different. It takes a good tuner to get these to spoolup right. Took me a little bit to figure out.
You end up with about 2500 dollars in them and that is what I sell them for.
The profit on the backend of this turbo is selling the gt3794.
In that turbo you balance the lly or a 10 blade 6.0 psd turbine to the 68mm 4094 compressor. Then you attach the stock lly turbine housing. If you sand balst the stock housing and ceramic coat the housing it is like a brand new turbo because it has brand new bearings etc.
You can sell those turbo's for around 1500 dollars. They are becoming very popular now.
There downside is higher drive pressure and the larger compressor inducer does not meet some rules in competition.
I hope this helps
You need a core lly turbo. You use the lly center and front, buy an 11 blade or batmo lly wheel, balance it to a gt40 turbine in the lly center housing. Then use the new gt40 turbine housing and vanes.
You will see the difference in the vane design and why the tuning is so drastically different. It takes a good tuner to get these to spoolup right. Took me a little bit to figure out.
You end up with about 2500 dollars in them and that is what I sell them for.
The profit on the backend of this turbo is selling the gt3794.
In that turbo you balance the lly or a 10 blade 6.0 psd turbine to the 68mm 4094 compressor. Then you attach the stock lly turbine housing. If you sand balst the stock housing and ceramic coat the housing it is like a brand new turbo because it has brand new bearings etc.
You can sell those turbo's for around 1500 dollars. They are becoming very popular now.
There downside is higher drive pressure and the larger compressor inducer does not meet some rules in competition.
I hope this helps
I think there may be a vendor that sell milled down vanes to clear the wheel, or they may be redesigned and higher flowing.
The pins on the lly turbine are for the 13 blade wheels and fin angle.
The gt40 wheel is 10 vane and the pitch is different. I have had the most success using the factory parts together.
I think other vendors on here have other combinations and they work very well also.
Once you have them side by side take some pictures and post them up. You will see the differences.
As far as how everything works it is trial and error.
Or you could just buy a turbo from a vendor that is already tested and proven. There are plenty of vendors here that are doing this already.
Mark Broviak - Danville Performance
Yellowchevy is a vendor
turbo performance
fleece performance
fingers (vanes)
Probably some others
Last edited:
It will spool slow and you won't have the power capability with the small compressor. Idc what anyone says a 4094 just spools slow. I would put the gt40 compressor with the gt37 exhaust. If your worried about the exhaust being restrictive then do a port job. Good spool up and top end power sounds like a win win. You'll only be able to push either turbo so far safely. If its a stock motor 600hp will be the tipping point.